langevitour: smooth interactive touring of high dimensions, demonstrated with scRNA-Seq data

langevitour displays interactive animated 2D projections of high-dimensional datasets. Langevin Dynamics is used to produce a smooth path of projections. Projections are initially explored at random. A “guide” can be activated to look for an informative projection, or variables can be manually positioned. After a projection of particular interest has been found, continuing small motions provide a channel of visual information not present in a static scatter-plot. langevitour is implemented in Javascript, allowing for a high frame rate and responsive interaction, and can be used directly from the R environment or embedded in HTML documents produced using R. The widget is demonstrated using single-cell RNA sequencing (scRNA-Seq) data. langevitour’s linear projections provide a less distorted view of this data than commonly used non-linear dimensionality reductions such as UMAP.